SAMSUNG CE104CF Service Manual Alignment & Adjustment

Samsung Electronics

5. Alignment and Adjustments

5-1 High Voltage Transformer

5-2 Low Voltage Transformer

5-3 Magnetron

5-1

1. Remove connectors from the transformer terminals
and check continuity.

2. Normal resistance readings are as follows:

(Room temperature = 20ûC)

Continuity checks can indicate only an open

filament or a shorted magnetron. To diagnose an
open filament or shorted magnetron :

1. Isolate the magnetron from the circuit by
disconnecting its leads.

2. A continuity check across the magnetron filament
terminals should indicate one ohm or less.

3. A continuity check between each filament terminal
and magnetron case should read open.

1. The low voltage transformer is located on the
control circuit board.

2. Remove the low voltage transformer from the
PCB Ass'y and check continuity.

3. Normal resistor reading is shown in the table.

PRECAUTION

1. High voltage is present at the high voltage terminals during any cook cycle.

2. It is neither necessary nor advisable to attempt measurement of the high voltage.

3. Before touching any oven components or wiring, always unplug the oven from its power source and discharge the high voltage
capacitor.

Filament Terminals

Primary
Terminals

MODEL

CE104CF

Secondary 94Ω ± 10%

Filament Shows Continuity
Primary 1.7Ω ± 10%

Terminals Resistance

1~2(Input) 195.4Ω
3~4(Output) 1.50Ω
5~6(Output) 0.73Ω

Cooling Fins

Gasket Plate

Magnetron Antenna

Samsung Electronics

5-4 High Voltage Capacitor

5-5 High Voltage Diode

5-6 Main Relay and Power Control Relay

5-7 Adjustment of Primary Switch, Door Sensing Switch and Monitor Switch

5-2

1. Check continuity of the capacitor with the meter set at the highest resistance scale.

2. Once the capacitor is charged, a normal capacitor shows continuity for a short time, and then indicates 9MΩ.

3. A shorted capacitor will show continuous continuity.

4. An open capacitor will show constant 9MΩ.

5. Resistance between each terminal and chassis should read infinite.

1. Isolate the diode from the circuit by disconnecting its leads.

2. With the ohm-meter set at the highest resistance scale, measure across the diode terminals. Reverse the
meter leads and read the resistance. A meter with 6V, 9V or higher voltage batteries should be used to
check the front-to back resistance of the diode (otherwise an infinite resistance may be read in both

directions). The resistance of a normal diode will be infinite in one direction and several hundred KΩ in

the other direction.

1. When mounting Primary switch and Interlock
Monitor switch to Latch Body, consult the
figure.

NOTE:No specific adjustment during

installation of Primary switch and Monitor
switch to the latch body is necessary.

2. When mounting the Latch Body to the oven
assembly, adjust the Latch Body by moving it so
that the oven door will not have any play in it.
Check for play in the door by pulling the door
assembly. Make sure that the latch keys move
smoothly after adjustment is completed.
Completely tighten the screws holding the Latch
Body to the oven assembly.

3. Reconnect to Monitor switch and check the
continuity of the monitor circuit and all latch
switches again by following the components test
procedures.

4. Confirm that the gap between the switch
housing and the switch actuator is no more than

0.5mm when door is closed.

1. The relays are located on the PCB Ass'y. Isolate them from the main circuit by disconnecting the leads.

2. Operate the microwave oven with a water load in the oven. Set the power level set to high.

3. Check continuity between terminals of the relays after the start pad is pressed.

Precaution

For continued protection against radiation hazard, replace parts in accordance with the wiring diagram and be sure to use the
correct part number for the following switches: Primary and door sensing switches, and the interlock monitor switch (replace all
together). Then follow the adjustment procedures below. After repair and adjustment, be sure to check the continuity of all
interlock switches and the interlock monitor switch.

Alignment and Adjustments

Door Open Door Closed

Primary switch ∞ 0
Monitor switch (COM-NC) 0 ∞
Monitor switch (COM-NO)

∞

0

Door Sensing switch

∞

0

Primary Interlock S/W

Door Sensing S/W

Interlock Monitor S/W

Lever Switch(A)

Lever Switch(B)

Key Door

Body Latch

Samsung Electronics 5-3

7. Normal temperature rise for this model is 9ûC to 11ûC at 'HIGH'.
NOTE 1: Variations or errors in the test procedure will cause a variance in the temperature rise.
Additional power test should be made if temperature rise is marginal.
NOTE 2: Output power in watts is computed by multiplying the temperature rise (step 5) by a factor of 90
times the of centigrade temperature.

4.187 x 1000 x ∆T+0.88xMcx(T2-T0)

Output Power =

46.5

46.5: Heating Time (sec)

4.187 : Coefficient for Water
1000 : Water (cc)

∆T : Temperature Rise (T2-T1)

Mc : Cylindrical borosilicate glass weight
To : Room temperature.

5-8 Output Power of Magnetron

Alignment and Adjustments

CAUTION

MICROWAVE RADIATION

PERSONNEL SHOULD NOT ALLOW EXPOSURE TO MICROWAVE RADIATION FROM MICROWAVE GENERATOR OR OTHER PARTS
CONDUCTING MICROWAVE ENERGY.

The output power of the magnetron can be measured by performing a water temperature rise test.
Equipment needed :
* Two 1-liter cylindrical borosilicate glass vessel (Outside diameter 190 mm)
* One glass thermometer with mercury column
NOTE: Check line voltage under load. Low voltage will lower the magnetron output. Make all temperature
and time tests with accurate equipment.

1. Fill the one liter glass vessel with water.

2. Stir water in glass vessel with thermometer, and record glass vessel's temperature ("T1", 10±1ûC).

3. After moving the water into another glass vessel, place it in the center of the cooking tray. Set the oven to high
power and operate for 48seconds exactly. (1.5 seconds included as a holding time of magnetron oscillation:)

4. When heating is finished, stir the water again with the thermometer and measure the temperature ("T2").

5. Subtract T1 from T2. This will give you the water temperature rise. (∆T)

6. The output power is obtained by the following formula;

The microwave heat distribution can be checked indirectly by measuring the water temperature rise at
certain positions in the oven:

1. Prepare five beakers made of 'Pyrex', having 100 milliliters capacity each.

2. Measure exactly 100milliliters off water load with a measuring cylinder, and pour into each beaker.

3. Measure the temperature of each water load. (Readings shall be taken to the first place of decimals.)

4. Put each beaker in place on the cooking tray as illustrated in figure below. Start heating.

5. After heating for 2 minutes, measure the water temperature in each beaker.

6. Microwave heat distribution rate can be calculated as follows:

Minimum

Temperature Rise

Heat Distribution = X 100(%)

Maximum

Temperature Rise

The result should exceed 65%.

5-9 Microwave Heat Distribution - Heat Evenness

D

D

D/4

D/4

D/4

D/4

Cooking Tray

Beaker

Samsung Electronics5-4

Alignment and Adjustments

1) Pour 275±15cc of 20±5ûC(68±9ûF) water in a
beaker which is graduated to 600cc, and place
the beaker in the center of the oven.

2) Start to operate the oven and measure the
leakage by using a microwave energy survey
meter.

3) Set survey meter with dual ranges to 2,450MHz.

4) When measuring the leakage, always use the 2
inch spacer cone with the probe. Hold the probe
perpendicular to the cabinet door. Place the
spacer cone of the probe on the door and/or
cabinet door seam and move along the seam, the
door viewing window and the exhaust openings moving the probe in a clockwise direction at a rate of 1
inch/sec. If the leakage testing of the cabinet door seam is taken near a corner of the door, keep the probe
perpendicular to the areas making sure that the probe end at the base of the cone does not get closer than 2
inches to any metal. If it gets closer than 2 inches, erroneous readings may result.

5) Measured leakage must be less than 4mW/cm2, after repair or adjustment.

1. PLATED MEAL

2.

CANNED FOOD

3. CASSEROLE / STEW

4. SOUP / SAUCE

5. BOILED POTATOES

6. FRESH VEGETABLES

7. FISH

8. ROAST BEEF

9. ROAST PORK

10.ROAST CHICKEN

AUTO REHEAT / COOK

5-13 Leakage Measuring Procedure

5-10 Procedure for Measurement of Microwave Energy Leakage

5-12

. Note on Measurement

5-11 Check for Microwave Leakage

5-13-1 Record keeping and notification after measurement

1) After adjustment and repair of a radiarion preventing device, make a repair record for the measured
values, and keep the data.

2) If the radiation leakage is more than 4 mW/§† after determining that all parts are in good condition,
functioning properly and the identical parts are replaced as listed in this manual notift that fact to ;

CENTRAL SERVICE CENTER

5-13-2 At least once a year have the microwave energy survey meter checked for accuracy by its manufacturer.

1. Remove the outer panel.

2. Pour 275±15cc of 20±5ûC(68±9ûF) water in a
beaker which is graduated to 600cc, and
place the beaker in the center of the oven.

3. Start the oven at the highest power level.

4. Set survey meter dual ranges to 2,450MHz.

5. Using the survey meter and spacer cone as
described above, measure arnear the
opening of magnetron, the surface of the air
guide and the surface of the wave guide as
shown in the following photo.( but avoid the
high voltage components.) The neading
should be less than 4mW/cm2.

1) Do not exceed the limited scale.

2) The test probe must be held on the grip of the handle, otherwise a false reading may result when the
operator's hand is between the handle and the probe.

3) When high leakage is suspected, do not move the probe horizontally along the oven surface; this may
cause damage to the probe.

4) Follow the recommendation of the manufacturer of the microwave energy survey meter.

Maximum allowable leakage is 5mW/cm2.
4mW/cm2is used to allow for measurement and meter accuracy

WARNING

AVOID THE HIGH VOLTAGE COMPONENTS.